Arduino IDE 2.3.6 hangs on startup (not the RAMDISK problem)

minus_plus · October 20, 2025, 7:26am

Hello.
Key information: I am installing IDE on a permanently offline computer (Windows 10).
It might be related to that, but I don't think it should be because I saw that some people use Arduino offline.
I ran the program from PowerShell, and this is my log (I don't see any messages related to the temporary folder there, so I assume that's not it.):

PS C:\Program Files\Arduino IDE> & '.\Arduino IDE.exe'
PS C:\Program Files\Arduino IDE>
Arduino IDE 2.3.6
Checking for frontend application configuration customizations. Module path: C:\Program Files\Arduino IDE\resources\app\lib\backend\electron-main.js, destination 'package.json': C:\Program Files\Arduino IDE\resources\app\package.json
Setting 'theia.frontend.config.appVersion' application configuration value to: "2.3.6" (type of string)
Setting 'theia.frontend.config.cliVersion' application configuration value to: "1.2.0" (type of string)
Setting 'theia.frontend.config.buildDate' application configuration value to: "2025-04-09T11:26:55.498Z" (type of string)
Frontend application configuration after modifications: {"applicationName":"Arduino IDE","defaultTheme":{"light":"arduino-theme","dark":"arduino-theme-dark"},"defaultIconTheme":"none","electron":{"windowOptions":{},"showWindowEarly":true,"splashScreenOptions":{},"uriScheme":"arduino-ide"},"defaultLocale":"","validatePreferencesSchema":false,"reloadOnReconnect":true,"uriScheme":"theia","preferences":{"window.title":"${rootName}${activeEditorShort}${appName}","files.autoSave":"afterDelay","editor.minimap.enabled":false,"editor.tabSize":2,"editor.scrollBeyondLastLine":false,"editor.quickSuggestions":{"other":false,"comments":false,"strings":false},"editor.maxTokenizationLineLength":500,"editor.bracketPairColorization.enabled":false,"breadcrumbs.enabled":false,"workbench.tree.renderIndentGuides":"none","explorer.compactFolders":false},"appVersion":"2.3.6","cliVersion":"1.2.0","buildDate":"2025-04-09T11:26:55.498Z"}
Starting backend process. PID: 8348
Showing main window early
Using browser-only version of superagent in non-browser environment
Configuration directory URI: 'file:///c%3A/Users/Ja/.arduinoIDE'
Configuring to accept webviews on '^.+\.webview\..+$' hostname.
2025-10-20T06:58:48.646Z root WARN Backend u.initialize took longer than the expected maximum 50 milliseconds: 61.4 ms [Finished 1.348 s after backend start]
2025-10-20T06:58:48.648Z root WARN Backend Object.initialize took longer than the expected maximum 50 milliseconds: 57.9 ms [Finished 1.348 s after backend start]
2025-10-20T06:58:48.648Z root INFO Backend a.initialize: 2.6 ms [Finished 1.348 s after backend start]
2025-10-20T06:58:48.648Z root INFO Backend a.initialize: 2.2 ms [Finished 1.348 s after backend start]
2025-10-20T06:58:48.648Z root INFO Backend u.initialize: 2.8 ms [Finished 1.349 s after backend start]
2025-10-20T06:58:48.654Z root WARN Backend l.initialize took longer than the expected maximum 50 milliseconds: 60.8 ms [Finished 1.351 s after backend start]
2025-10-20T06:58:48.668Z root INFO configured all backend app contributions
2025-10-20T06:58:48.669Z root INFO Backend l.onStart: 2.6 ms [Finished 1.374 s after backend start]
2025-10-20T06:58:48.670Z root INFO Backend d.onStart: 0.2 ms [Finished 1.374 s after backend start]
2025-10-20T06:58:48.672Z root INFO Backend a.onStart: 0.8 ms [Finished 1.375 s after backend start]
2025-10-20T06:58:48.672Z config INFO >>> Initializing CLI configuration...
2025-10-20T06:58:48.673Z root INFO Backend x.onStart: 0.7 ms [Finished 1.376 s after backend start]
2025-10-20T06:58:48.673Z config INFO Loading CLI configuration from c:\Users\Ja\.arduinoIDE\arduino-cli.yaml...
2025-10-20T06:58:48.673Z daemon INFO Starting daemon from C:\Program Files\Arduino IDE\resources\app\lib\backend\resources\arduino-cli.exe...
2025-10-20T06:58:48.673Z root INFO Backend w.onStart: 0.8 ms [Finished 1.377 s after backend start]
2025-10-20T06:58:48.673Z discovery-log INFO start
2025-10-20T06:58:48.673Z discovery-log INFO start new deferred
2025-10-20T06:58:48.673Z root INFO Backend v.onStart: 0.7 ms [Finished 1.378 s after backend start]
2025-10-20T06:58:48.673Z root INFO Backend a.onStart: 0.3 ms [Finished 1.379 s after backend start]
2025-10-20T06:58:48.690Z root WARN The local plugin referenced by local-dir:/c%3A/Users/Ja/.arduinoIDE/plugins does not exist.
2025-10-20T06:58:48.690Z root WARN The local plugin referenced by local-dir:/c%3A/Users/Ja/.arduinoIDE/deployedPlugins does not exist.
2025-10-20T06:58:48.691Z root WARN The local plugin referenced by local-dir:C:\Users\Ja\.arduinoIDE\plugins does not exist.
2025-10-20T06:58:48.696Z root INFO Theia app listening on http://127.0.0.1:61168.
2025-10-20T06:58:48.696Z root INFO Finished starting backend application: 23.0 ms [Finished 1.402 s after backend start]2025-10-20T06:58:48.717Z config INFO Loaded CLI configuration: {"board_manager":{"additional_urls":[]}}
2025-10-20T06:58:48.717Z config INFO Loading fallback CLI configuration to get 'directories.data' and 'directories.user'2025-10-20T06:58:48.917Z root INFO Resolve plugins list: 240.6 ms [Finished 1.622 s after backend start]
2025-10-20T06:58:49.659Z daemon INFO time="2025-10-20T08:58:49+02:00" level=info msg="arduino-cli version 1.2.0"
time="2025-10-20T08:58:49+02:00" level=info msg="Using config file: c:\\Users\\Ja\\.arduinoIDE\\arduino-cli.yaml"
time="2025-10-20T08:58:49+02:00" level=info msg="Executing `arduino-cli daemon`"
Daemon is now listening on 127.0.0.1:61169
{"IP":"127.0.0.1","Port":"61169"}
2025-10-20T06:58:49.659Z daemon INFO Daemon is running.
2025-10-20T06:58:49.964Z config INFO Loaded fallback CLI configuration: {"directories":{"user":"C:\\Users\\Ja\\Documents\\Arduino","data":"C:\\Users\\Ja\\AppData\\Local\\Arduino15"}}
2025-10-20T06:58:49.964Z config INFO Merged CLI configuration with the fallback: {"directories":{"user":"C:\\Users\\Ja\\Documents\\Arduino","data":"C:\\Users\\Ja\\AppData\\Local\\Arduino15"},"board_manager":{"additional_urls":[]}}
2025-10-20T06:58:49.964Z config INFO Loaded the CLI configuration.
2025-10-20T06:58:49.977Z config INFO Mapped the CLI configuration: {"dataDirUri":"file:///c%3A/Users/Ja/AppData/Local/Arduino15","sketchDirUri":"file:///c%3A/Users/Ja/Documents/Arduino","additionalUrls":[],"network":"none","locale":"en"}
2025-10-20T06:58:49.977Z config INFO Validating the CLI configuration...
2025-10-20T06:58:49.977Z config INFO The CLI config is valid.
2025-10-20T06:58:49.977Z config INFO <<< Initialized the CLI configuration.
2025-10-20T06:58:50.195Z daemon INFO time="2025-10-20T08:58:50+02:00" level=info msg="Checking signature" index="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\package_index.json" signatureFile="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\package_index.json.sig" trusted=true
2025-10-20T06:58:50.241Z daemon INFO time="2025-10-20T08:58:50+02:00" level=info msg="Loading hardware from: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages"
time="2025-10-20T08:58:50+02:00" level=info msg="Loading package esp8266 from: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware"
2025-10-20T06:58:50.327Z daemon INFO time="2025-10-20T08:58:50+02:00" level=info msg="Adding monitor tool" protocol=serial tool="builtin:serial-monitor"
time="2025-10-20T08:58:50+02:00" level=info msg="Loaded platform" platform="esp8266:esp8266@3.0.2"
time="2025-10-20T08:58:50+02:00" level=info msg="Checking existence of 'tools' path: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools"
time="2025-10-20T08:58:50+02:00" level=info msg="Loading tools from dir: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools"
time="2025-10-20T08:58:50+02:00" level=info msg="Loaded tool" tool="esp8266:mklittlefs@3.0.4-gcc10.3-1757bed"
time="2025-10-20T08:58:50+02:00" level=info msg="Loaded tool" tool="esp8266:mkspiffs@3.0.4-gcc10.3-1757bed"
time="2025-10-20T08:58:50+02:00" level=info msg="Loaded tool" tool="esp8266:python3@3.7.2-post1"
time="2025-10-20T08:58:50+02:00" level=info msg="Loaded tool" tool="esp8266:xtensa-lx106-elf-gcc@3.0.4-gcc10.3-1757bed"
time="2025-10-20T08:58:50+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/tools/ctags-5.8-arduino11-pm-i686-mingw32.zip"
2025-10-20T06:58:50.417Z daemon INFO time="2025-10-20T08:58:50+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/discovery/serial-discovery/serial-discovery_v1.3.2_Windows_64bit.zip"
time="2025-10-20T08:58:50+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/discovery/mdns-discovery/mdns-discovery_v1.0.6_Windows_64bit.zip"
time="2025-10-20T08:58:50+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/monitor/serial-monitor/serial-monitor_v0.11.0_Windows_64bit.zip"
time="2025-10-20T08:58:50+02:00" level=info msg="Loading tools from dir: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\builtin\\tools"
2025-10-20T06:58:50.421Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:ctags@5.8-arduino11 tool: Get "https://downloads.arduino.cc/tools/ctags-5.8-arduino11-pm-i686-mingw32.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:50.427Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:serial-discovery@1.3.2 tool: Get "https://downloads.arduino.cc/discovery/serial-discovery/serial-discovery_v1.3.2_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:50.435Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:mdns-discovery@1.0.6 tool: Get "https://downloads.arduino.cc/discovery/mdns-discovery/mdns-discovery_v1.0.6_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:50.438Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:serial-monitor@0.11.0 tool: Get "https://downloads.arduino.cc/monitor/serial-monitor/serial-monitor_v0.11.0_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:50.441Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: reading directory C:\Users\Ja\AppData\Local\Arduino15\packages\builtin\tools: open C:\Users\Ja\AppData\Local\Arduino15\packages\builtin\tools: System nie mo┼╝e odnale┼║─ç okre┼Ťlonej ┼Ťcie┼╝ki.
2025-10-20T06:58:50.443Z daemon INFO time="2025-10-20T08:58:50+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2\\libraries" isSingleLibrary=false location=platform
time="2025-10-20T08:58:50+02:00" level=info msg="Loading libraries index file" index="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\library_index.json"
2025-10-20T06:58:50.470Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
2025-10-20T06:58:50.470Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
2025-10-20T06:58:50.471Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
2025-10-20T06:58:50.471Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
2025-10-20T06:58:50.729Z root INFO creating connection for 1
2025-10-20T06:58:51.329Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\libraries" isSingleLibrary=false location=ide
time="2025-10-20T08:58:51+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\Documents\\Arduino\\libraries" isSingleLibrary=false location=user
2025-10-20T06:58:51.331Z root INFO Deploy plugins list: 2655.8 ms [Finished 4.037 s after backend start]
2025-10-20T06:58:51.785Z root ERROR The primary packages indexes are missing. Running indexes update before initializing the core gRPC client The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed

2025-10-20T06:58:51.789Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Updating index" url="https://downloads.arduino.cc/packages/package_index.tar.bz2"
2025-10-20T06:58:51.791Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/packages/package_index.tar.bz2"
2025-10-20T06:58:51.798Z root INFO core-client-provider [platform-index] Downloading index: package_index.tar.bz2

2025-10-20T06:58:51.804Z root ERROR Failed to update platform indexes. Error: 13 INTERNAL: Some indexes could not be updated.
    at t.callErrorFromStatus (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:3089094)
    at Object.onReceiveStatus (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6681994)
    at Object.onReceiveStatus (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:2571739)
    at C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:4307911
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11)
for call at
    at s.makeServerStreamRequest (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6681761)
    at s.updateIndex (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:3088187)
    at C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6284829
    at C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6285177
    at new Promise (<anonymous>)
    at y.doUpdateIndex (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6285156)
    at y.updatePlatformIndex (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6284801)
    at y.updateIndex (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6284169)
    at y.initInstanceWithFallback (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6282462)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
2025-10-20T06:58:51.828Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Checking signature" index="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\package_index.json" signatureFile="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\package_index.json.sig" trusted=true
2025-10-20T06:58:51.830Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loading hardware from: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages"
2025-10-20T06:58:51.831Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loading package esp8266 from: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware"
2025-10-20T06:58:51.882Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Adding monitor tool" protocol=serial tool="builtin:serial-monitor"
2025-10-20T06:58:51.883Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loaded platform" platform="esp8266:esp8266@3.0.2"
2025-10-20T06:58:51.883Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Checking existence of 'tools' path: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools"
2025-10-20T06:58:51.884Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loading tools from dir: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools"
2025-10-20T06:58:51.885Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loaded tool" tool="esp8266:mklittlefs@3.0.4-gcc10.3-1757bed"
2025-10-20T06:58:51.885Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loaded tool" tool="esp8266:mkspiffs@3.0.4-gcc10.3-1757bed"
2025-10-20T06:58:51.886Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loaded tool" tool="esp8266:python3@3.7.2-post1"
2025-10-20T06:58:51.886Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loaded tool" tool="esp8266:xtensa-lx106-elf-gcc@3.0.4-gcc10.3-1757bed"
2025-10-20T06:58:51.887Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/monitor/serial-monitor/serial-monitor_v0.11.0_Windows_64bit.zip"
2025-10-20T06:58:51.894Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/tools/ctags-5.8-arduino11-pm-i686-mingw32.zip"
2025-10-20T06:58:51.896Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:serial-monitor@0.11.0 tool: Get "https://downloads.arduino.cc/monitor/serial-monitor/serial-monitor_v0.11.0_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:51.900Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/discovery/serial-discovery/serial-discovery_v1.3.2_Windows_64bit.zip"
2025-10-20T06:58:51.909Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:ctags@5.8-arduino11 tool: Get "https://downloads.arduino.cc/tools/ctags-5.8-arduino11-pm-i686-mingw32.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:51.919Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Starting download" url="https://downloads.arduino.cc/discovery/mdns-discovery/mdns-discovery_v1.0.6_Windows_64bit.zip"
2025-10-20T06:58:51.927Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:serial-discovery@1.3.2 tool: Get "https://downloads.arduino.cc/discovery/serial-discovery/serial-discovery_v1.3.2_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:51.935Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loading tools from dir: C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\builtin\\tools"
2025-10-20T06:58:51.956Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2\\libraries" isSingleLibrary=false location=platform
2025-10-20T06:58:51.958Z daemon INFO time="2025-10-20T08:58:51+02:00" level=info msg="Loading libraries index file" index="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\library_index.json"
2025-10-20T06:58:51.962Z root ERROR Detected an error response during the gRPC core client initialization: code: 13, message: downloading builtin:mdns-discovery@1.0.6 tool: Get "https://downloads.arduino.cc/discovery/mdns-discovery/mdns-discovery_v1.0.6_Windows_64bit.zip": dial tcp: lookup downloads.arduino.cc: no such host
2025-10-20T06:58:51.964Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: reading directory C:\Users\Ja\AppData\Local\Arduino15\packages\builtin\tools: open C:\Users\Ja\AppData\Local\Arduino15\packages\builtin\tools: System nie mo┼╝e odnale┼║─ç okre┼Ťlonej ┼Ťcie┼╝ki.
2025-10-20T06:58:51.964Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
2025-10-20T06:58:51.965Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
2025-10-20T06:58:51.965Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
2025-10-20T06:58:51.965Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
2025-10-20T06:58:52.509Z daemon INFO time="2025-10-20T08:58:52+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\AppData\\Local\\Arduino15\\libraries" isSingleLibrary=false location=ide
2025-10-20T06:58:52.510Z daemon INFO time="2025-10-20T08:58:52+02:00" level=info msg="Adding libraries dir" dir="C:\\Users\\Ja\\Documents\\Arduino\\libraries" isSingleLibrary=false location=user
2025-10-20T06:58:52.800Z root WARN Frontend a.configure took longer than the expected maximum 100 milliseconds: 307.9 ms [Finished 4.062 s after frontend start]
2025-10-20T06:58:52.873Z root WARN A command editor.action.toggleStickyScroll is already registered.
Opening channel for service path '/services/electron-window'.
Opening channel for service path '/services/ide-updater'.
2025-10-20T06:58:52.995Z root WARN Frontend keybindings.onStart took longer than the expected maximum 100 milliseconds: 111.2 ms [Finished 4.233 s after frontend start]
2025-10-20T06:58:53.162Z root INFO Start frontend contributions: 790.9 ms [Finished 4.392 s after frontend start]
2025-10-20T06:58:53.164Z root INFO Changed application state from 'init' to 'started_contributions'.
2025-10-20T06:58:53.183Z root INFO Changed application state from 'started_contributions' to 'attached_shell'.
2025-10-20T06:58:53.184Z root INFO >>> Restoring the layout state...
2025-10-20T06:58:53.248Z root INFO [1f6eec37-38cc-43b7-bba1-4f327718deba] Waiting for backend deployment: 130.0 ms [Finished 4.508 s after frontend start]
2025-10-20T06:58:53.989Z root ERROR Uncaught Exception:  Error: The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed

2025-10-20T06:58:53.989Z root ERROR Error: The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not installed
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not installed

    at C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6283973
    at y.evaluateErrorStatus (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6283989)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async a.<anonymous> (C:\Program Files\Arduino IDE\resources\app\lib\backend\main.js:2:6283659)
2025-10-20T06:58:55.337Z root INFO [hosted-plugin: 3532] PLUGIN_HOST(3532) starting instance
[Object: null prototype] {}
2025-10-20T06:58:56.610Z root INFO [1f6eec37-38cc-43b7-bba1-4f327718deba] Sync of 23 plugins: 3365.3 ms [Finished 7.873 s after frontend start]

Any help will be welcome.

sterretje · October 20, 2025, 10:03am

On the first run, the IDE wants to download some additional files. No internet means that it can not download those files.

A possible workaround is to use a computer (same operating system) with internet access, install what you need and next copy the Arduino15 folder to the offline system.

You probably also have a need for some 3rd party libraries. Download those using the online system and copy them to the offline system. You can always do the library stuff afterwards.

minus_plus · October 20, 2025, 2:27pm

I had such a plan, but only after successfull installation the Arduino.
I thought the installer was standalone (full installer, not internet installer). But apparently I was mistaken.
I did as you said, meaning I copied those files despite the Arduino not working, and it start!
So, thank you very much! (for this step)

But I have another problem.
Some of my project compile fine (and works after flasfing).
But most of those (that use libraries) do not compile. Arduino does not see the libraries.
Original working Arduino in online computer have libraries in Arduino15/staging folder. Is this correct location? Offline computer don't have this folder (staging) after Arduino installation. I copied it, but maybe the offline IDE doesn't recognize that the libraries are there and is searching for them elsewhere.
I know this thread:

But my libraries is not in Users/xxxx/Documents/Arduino but in Arduino15/staging.

Topic		Replies	Views
IDE hangs on startup when used on machine without Internet access IDE 2.x	3	136	September 13, 2025
IDE hangs on startup: "connectex: A connection attempt failed because the connected party did not properly respond after a period of time ..." IDE 2.x	8	2888	May 19, 2024
IDE hangs on startup: "Error loading hardware platform: discovery builtin:serial-discovery not found" IDE 2.x	4	492	May 10, 2024
IDE hangs on startup: "library_index.json: The system cannot find the file specified" IDE 2.x	5	1062	September 12, 2024
IDE hangs on startup: "Error loading hardware platform: discovery builtin:serial-discovery not installed" IDE 2.x	3	824	May 10, 2024

Arduino IDE 2.3.6 hangs on startup (not the RAMDISK problem)

Related topics